To limit the probability of structural failure at
the point of attachment of stairs, which could lead to an inability
to support vertical building loads or lateral earth loads, which could
- structural failure of the stairs, or
- where the foundation wall encloses interior spaces,
compromised integrity of elements supported or protected by foundations,
which could lead to the ingress of moisture from the ground, which
could lead to deterioration.
This is to limit the probability of
harm to persons.